Patent GB-439137-A (GB)
Title: Improvements in door locks
IPC: E05B17/22
Filed: 1934-12-06
Abstract: 439,137. Door locks. PLATIN, G. A., 10, Gamla Kungsgatan, Kalmar, Sweden. Dec. 6, 1934, No. 35091. Convention date, Dec. 7, 1933. [Class 44] A door lock is provided with two rotary handles on opposite sides of the door one of which moves the bolt rectilinearly and the other tilts it, and a movable abutment on the door-post co-operates with the lock bolt in such a manner that it occupies different positions according to which handle has been used to lock the door and in one of these positions prevents the opening of the door by one of the handles. The door may give access to a room so that when fastened by using the inside handle the door can only be opened from the inside and the movable abutment may actuate an electric switch for lighting the room as long as it is occupied. A lock bolt 28 is slidable longitudinally upon a guide pin 36 by a lever 2 connected to the spindle of an inside handle 1, and is tiltable about the pin 36 by a lever 3 on the spindle of an outside handle. When the bolt is tilted by the outside handle it can clear a lip 7 of an opening in a keeper 5, but as the door closes the bolt displaces a pivoted plate 6, Fig. 5, and opens a switch 32 to put out a light. When the door is opened the switch is closed and when reclosed by using the inside handle the plate 6 is not moved as the bolt is now retracted, and when the handle is released the bolt engages behind the plate 6 which prevents the bolt from leaving the keeper when tilted by the outside handle. Fig. 13 shows a modified keeper in which a plate 28 corresponding to the plate 6 is pivoted about a vertical axis 29 and carries a switch arm 93 co-operating with two contacts 95, 96. Fig. 7 shows a modification in which the outside handle moves a lever 14 to slide the bolt on two pins 40, 41, outward movement displacing a pivoted plate 19 to open a switch 32. The pins 40, 41 are carried by a plate 13 pivoted about the spindle of the inner handle 16 and normally maintained stationary by a detent 15. The spindle of the inner handle, which has a lost-motion connection with the outer handle, carries an arm 17, and as the handle is turned this arm first disengages the detent 15 and then, by engaging a pin 44 on the plate 13, tilts the plate until the bolt is wholly within the casing. On release of the handle a spring 45, connected to the arm 17, returns the parts to their normal position and a notch 18 in the bolt hooks over the plate 19 without displacing it. The switch 32 therefore remains closed, and the bolt cannot be withdrawn by the outer handle. The Specification as open to inspection under Sect. 91 comprises also the following subject-matter. A bolt 147, Fig. 13 (Cancelled) is connected at 148 to a follower 146 on a spindle 140 connected to an inner handle and is connected by a link 50 to a follower 149 on a separate spindle 141 of the outer handle. Pins 52, 53 act as stops for the two followers. Movement of the follower 149 tilts the bolt about the pin 148 and movement of the follower 146 causes a longitudinal displacement under control of the link 50 which contacts with the pin 52 at the limit of its rearward movement. To give access to the room in emergency the spindle 140 may have a square end engageable by a key inserted through the front plate of the lock. Figs. 19 (Cancelled), and 22 (Cancelled) show a modified switch and locking mechanism in which a switch member 72 is in its closed position when a plate 65 pivoted on a vertical spindle 66 is urged against the outer opening of the keeper casing by a spring 67. When displaced by the bolt in closing the door from the outside a projection 75 on the plate moves the member 72 to open the switch. In order to prevent the light from being switched on until the door is closed from the inside, the plate 65 may be set so as to take up an intermediate position when the door is first opened. The bolt in this case is provided with a bevelled end to engage behind the plate as the bolt is slid outwards by the inner handle so as to force the plate into its position against the outer opening of the casing and allow the switch 72 to close. To effect this setting, a cam 79, which normally prevents a spring 77 from acting on the plate, is moved by unscrewing a set-screw 80, whereupon the spring 77, which is stronger than the spring 67, presses back the plate into the required intermediate position. This subject-matter does not appear in the Specification as accepted.